The decimal separator is a period. Large or small numbers can be written as "1.11e10" or "-1.11e-10".
pc to AU, meters, and lightyear (LY) (and vice versa)
Stellar speeds from parallax, distance and radial speed
Conversion of mass loss rate to number density at inner boundary (IB)
Conversion of parallax to distance [pc]
The Strömgren radius